What it delivers
The Rheem RTEX-08 8 kW Point-of-Use Tankless Water Heater is a point-of-use electric tankless rated at 8 kW on 240 volts.
Flow depends on how cold the incoming water is. Our estimate from its input: 1.2 GPM at a 45°F rise, falling to 0.8 GPM at 70°F, which is less than one 2 GPM shower on a cold-climate winter day. Check your house in the planner.
At 240 volts 8 kW is about 33 amps. The maker calls for one- 40‑amp double‑pole breaker. A licensed electrician confirms the panel, the service and the wire before it goes in.
Small units like this suit one sink or a low-flow shower close by; at a kitchen sink's 1.5 GPM the water won't rise as far.
Also on the listing: features: ON/OFF Dial Control and Adjustable Digital Temperature Display; material: Stainless Steel; model: RTEX-08; warranty: Limited Warranty - 5 Years Leaks, 1 Year Parts.
The listing gives dimensions of 8.25 in (W) x 12.63 in (H) and fittings, aerators in the box.
Warranty, per the listing: Limited Warranty - 5 Years Leaks, 1 Year Parts.
Right unit for this house?
Install it when
- One sink or a low-flow shower
- A far bathroom with a long wait for hot water
Look at another unit when
- Whole-house hot water
- Kitchen sinks at full flow in cold climates
Strengths and trade-offs
Strengths
- 8 kW
- No venting or gas line
- Breakers stated by the maker
Trade-offs
- Flow drops with cold inlet water
Install limits
- Figures are the maker's or seller's own. Flow at a rise is our estimate from the input; gas, venting and electrical work needs a licensed professional.
Rated performance
Every figure below comes from the source shown in brackets. Where the maker doesn't state something, we say so instead of estimating.
| Model number | RTEX-08 | Retailer |
|---|---|---|
| Tank | 1.95 gal | Retailer |
| Dimensions (seller) | 8.25"W x 12.63"H | Retailer |
| Features (seller) | ON/OFF Dial Control and Adjustable Digital Temperature Display | Retailer |
| Power | 8 kW | Retailer |
| Voltage | 240 V | Retailer |
| Material | Stainless Steel | Retailer |
| Warranty | Limited Warranty - 5 Years Leaks, 1 Year Parts | Retailer |
| Breakers (maker) | one- 40‑amp double‑pole breaker | Retailer |
Rival units at this flow
More point-of-use water heaters rated for similar demand
- Stiebel Eltron 200067 3.5 kW Point-of-Use Tankless Water Heater
- Titan N85 8.5 kW Point-of-Use Tankless Water Heater
- Stiebel Eltron DHX 6-2 Trend 6 kW Point-of-Use Tankless Water Heater
- Stiebel Eltron DHC 8-2 7.2 kW Point-of-Use Tankless Water Heater
Full point-of-use water heaters spec grid · Every Rheem unit in the catalog
Final verdict
A practical point-of-use electric tankless for one sink or a low-flow shower.
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